1. Technical Field
The present invention is related to a tension balancer for supporting the tension of a substation facility power cable etc.
2. Description of the Related Art
A power cable (bus line) 3 in substation facilities is elevated by a fixed tension between two steel structures 2. The tension at this time is generally a high tension of around 500 kgf. Therefore, breaks in the elevated wire due to shaking caused by earthquakes, transformation of the shape of steel structure parts and damage to dead-end insulators may be generated in the bus line 3 which does not take up any extra tension. Here, a tension balancer is provided as a device for stabilizing the state of a high tension. Although not used in substation facilities, a general tension balancer (For example, refer to Japanese Laid Open Patent 2000-158981) which is used for supporting the tension of elevated train cables (referred to as train cables below), is explained based on the diagrams. FIG. 9 shows the structure of a general train cable tension balancer 100 used for supporting the tension of train cables. In addition, FIG. 10 is an approximate schematic diagram of a pillar side connection part of the train cable tension balancer 100.
The train power cable tension balancer 100 is arranged with a plurality of telescopic inner pipes 103, and because stroke movement of the plurality of inner pipes 101 is produced when an extra tension is applied, a sufficient setting space is required.
In addition, the train power cable tension balancer 100 is arranged between a train power cable pillar and a train power cable and is used for supporting a specific tension. Here, because a train power cable is elevated outside, it receives the effects of wind etc. In strong winds, the train power cable is sometimes twisted. In this case, this twisting is transferred to the train power cable tension balancer 100 and the inner pipe 103 or hollow rod 104 within the train power cable tension balancer 100 are rotated. In order to prevent this rotation, a part such as a block shaped stopper 113 is required. In the case where this part is not arranged, the twisting of the train power cable is transferred to the rotation of the inner pipe 103 and it is no longer possible to stop the twisting of the train power cable. In order to stop the twisting, a rotation prevention part is required on each of the plurality of inner pipes 103 which are arranged in a telescopic shape resulting in an increase in costs and complex assembly.